SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43a5acef106e4ee2f2f5635ca8220e4cccb9c2bf5be539b5a557e5761157c722' 
  AND token = 'wC8Csz54FiSWR1KqJbaj86CwGO3ANSKglXbDR+N6Dk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}